1. Field of the Invention
Passivated heterojunction bipolar transistor (HBT) uses common mask to self-align all critical dimensions while also passivating emitter periphery.
2. Prior Art
U.S. Pat. Nos. 4,731,340 and 4,996,165 to Chang et al. best represent the known published prior art. The latter patent discloses a self-aligned dielectric assisted planarization process useful in planarizing the present invention, and the former patent discloses a dual lift-off self-aligning process for making HBTs, also useful in the process of the present invention. Dual lift-off process lifts off metal and dielectric, simultaneously. All inventions are commonly owned, and the inventors thereof are employed by the common assignee.